Hi Expander !!
My current IS133 is the 2008 model (w85), wider than your 2007 (w80) board so I think the behaviour would be different.
I use it only with a 9.0 code red (perfect for the board) and the ideal range in my opinion is between 10/15 knots for blasting with a sweet ride, and 12/17 for racing (the board donīt stop at turns and you can manage up to 18/20 ocassional gusts).
When the wind goes up I jump to the Is111/7.7 Code Red combo
The supplied 52 cm fin works decently and the board really fly (Is an amazing apparent wind generator) I tried samaller fins (DB SL2 46 for example) but didnīt work for me .
I guess that the new 2009 model will have more speed a higher range (more control at higher winds) because of the double wingers
My weight is 87 KG and my height is 1.83m